Extrusion device, and method for kneading resin raw material

Provided is an extrusion device by which energy discharged and discarded by a cooling means provided in the extrusion device is used within the same device, and energy usage efficiency is improved. Also provided is a method for kneading a resin raw material. An extrusion device 10 comprises: a cylinder 12 having an upstream area 12UA and a downstream area 12DA; a resin raw material supply unit 11 provided at the upstream area 12UA side of the cylinder 12; a screw disposed inside the cylinder 12 to convey and knead the resin raw material; and a resin raw material discharge part 15 provided at the downstream area 12DA side of the cylinder 12. The extrusion device 10 has: a heating means 14 provided in the upstream area 12UA of the cylinder to heat the resin raw material; a cooling means 16 provided in the downstream area 12DA of the cylinder to cool the cylinder 12; and piping 17 that is connected to the cooling means 16 and is disposed so as to connect the upstream area 12UA and the downstream area 12DA of the